In PHP, is the following logic allowed
If (x && y)
//Do A
Elseif (x)
// Do B
Elseif (y)
// Do C
Else
// Do D
Basically, are you allowed to use more than one elseif?
Yes:
if ($x && $y) {
//Do A
} else if ($x) {
// Do B
} else if ($y) {
// Do C
} else {
// Do D
}
Another format useful for HTML files
<?php if ($x && $y): ?>
Element A
<?php elseif ($x): ?>
Element B
<?php elseif ($y): ?>
Element C
<?php else: ?>
Element D
<?php endif;?>
Yes, although if the test is simple ($a == $b), use a switch instead:
switch ($a) {
case $b:
break;
case $c:
break;
default:
//Like else
}
Yes. Please see http://us3.php.net/elseif and http://us3.php.net/elseif.
You can use
if($x)
// for one line of code
elseif($y)
// also for one line of code
if($x) {
// for more than
// one line of code
} elseif($y) {
// also for multi-
// line codes
}
and
if($x):
// multi-line
endif;
yup
if(this == this && this == this){
//this and that
}else if(this == that || this == that){
//this or that
}else{
//anything else
}
Related
I need to implement 3 'if conditions' in my script, i've looked it up online but I can only find solutions up to 2 if's like below
<?
if (condition 1){
do something;
}
elseif (condition 2){
do something else;
}
else {
do this last;
}
?>
but I would need something like this:
if (condition 1) { do this };
else if (condition 2) {do that};
or else if (condition 3) {do that};
else (do this)
How do I go about this?
simply
if(condition){
}
else if(condition){
}
else if(condition){
}
else{
}
you can use switch case statements too. you can use else if as many as you want. Each condition inside if() can accept OR and AND operators as || for OR and && for AND you can use.
if (condition 1) { do this
} else if (condition 2) {do that
} else if (condition 3) {do that
} else { do this }
alternatively if you want to check one variable each time you can use a switch for example
$myvar = 5;
switch($myvar){
case 1:
//do this
break;
case 2:
//do that
break;
case 3:
//do that
break;
default:
//do this
}
You can use this construction
if ( $a == $b ) {
// something...
} else if ( $a == $c ) {
// something...
} else if ( $a == $d ) {
// something...
} else {
// otherwise...
}
But if all of the conditions are ( $a equals to something ) it's better to use switch ... case:
switch ( $a ) {
case $b:
// something...
break;
case $c:
// something...
break;
case $d:
// something...
break;
default:
// otherwise...
break;
}
Solution 1
Using many elseif statements as you want.
Use this solution when your conditions are complex, or comparing different variables.
if (/*condition 1*/) {
// Action to condition 1
} else if (/*condition 2*/) {
// Action to condition 2
} else if (/*condition 3*/) {
// Action to condition 3
} else if (/*condition n*/) {
// Action to condition n
} else {
// Action when no conditions match.
}
Solution 2
Using switch statement:
Use this condition when you want to compare a variable against constant values:
switch ($age) {
case 0:
return 'You are a baby';
break;
case 18:
return 'You are 18 years old';
break;
case 21:
case 22:
case 23:
return 'You are too old';
default:
return 'Unexpected age :(';
}
How about using the or operator, ||:
if (condition 1) { do this }
else if (condition 2 || condition 3) {do that}
else {do this}
An example:
<?php
function testCondition($a, $b) {
if ($a == $b) {
print ("They are the same<br />\n");
}
else if ($a == "a" || $b == "b") {
print ("One is the same as its letter<br />\n");
}
else {
print ("They are some other sort<br />\n");
}
}
testCondition("c","c");
testCondition("a","c");
testCondition("a","b");
testCondition("d","e");
?>
Outputs:
They are the same
One is the same as its letter
One is the same as its letter
They are some other sort
I have the same problem as first stated here. I have four variables but the second one is skipped and only 1,3, and 4 work. Why?
if(empty($fromName) or empty($fromEmail) or empty($subject) or empty($comments)) {
echo 'You cannot submit the form with empty fields. Please correct the form and resubmit.';
return false;
}
elseif($fieldDelete == "Delete this text!"){
echo "Delete the contents of the fourth field before submitting.";
return false;
}
elseif (($fromName == "Curtisvien") || ($fromName == "Thomastymn") || ($fromName == "RichardMark")) {
echo "Failed. Please try again.";
return false;
}
else {
$flgchk = mail ("$to", "$subject", "$message", "$headers");
$imgfile = "images/NatMap logo2.gif";
$handle = fopen($filename, "r");
$imgbinary = fread(fopen($imgfile, "r"), filesize($imgfile));
echo '<img src="data:image/gif;base64,' . base64_encode($imgbinary) . '" width=427 height=72 />';
echo "\n<br />\n<br />Thank You! An e-mail has been sent to the National Map web team and they will get back to you in the next 24-48 hours.";
}`enter code here`
How can display if if x=john or bond results you name is john or bond
<?php
if ($x == "john")
{
?>
you name is john or bond
<?php } ?>
if ($x == "john" || $x == "bond")
{
// do stuff
}
Or if you have many names you can use other structures like switch():
switch ($x)
{
case "john":
case "bond":
// do something
break;
default:
// or else do this
}
You can also use in_array() if you have a dynamic list of names or if you just feel like its more readable:
if (in_array($x, ["john", "bond"]))
{
// do stuff
}
Try this:
<?php
$x="bond";
//$x="john";
if ($x == "john" or $x == "bond") {
echo "Your name is ".$x;
}
?>
When the user introduces a letter and clicks on submit the script shall return a name that starts with that letter, I wrote it using a Switch/Case structure, now I need to write it using if/elseif/else.
The problem is that no matter what letter I introduce on the Textbox I'll always get the return for A (Aberdefia - Anacleto)
$nombrador=$_POST['nombrador'];
$nombrador=strtoupper($nombrador);
if ($nombradorIf = 'A') {
echo "Aberdefia - Anacleto";
} elseif ($nombradorIf = 'B') {
echo "Brígida - Brígido";
} else {
echo "Is that even a letter?";
}
The code for the letters C to Z is just like the one for A and B.
You need == for comparison, = is for assignment, and === is for identical or same type.
Also, you used $nombrador when assigning and $nombradorIf when comparing, resulting in an undefined variable.
if ($nombrador == 'A') {
echo "Aberdefia - Anacleto";
} elseif ($nombrador == 'B') {
echo "Brígida - Brígido";
} else {
echo "Is that even a letter?";
}
Thus, $nombrador == 'A' means $nombrador is equal to A.
And, $nombrador = 'A' means to assign A to $nombrador.
More information at http://php.net/manual/en/language.operators.comparison.php.
Hope this helps, thanks!
== is the conditional operator = is assigning operator
if ($nombrador == 'A') {
echo "Aberdefia - Anacleto";
} elseif ($nombrador == 'B') {
echo "Brígida - Brígido";
} else {
echo "Is that even a letter?";
}
Try this code
$nombrador=$_POST['nombrador'];
$nombrador=strtoupper($nombrador);
if ($nombrador == 'A') {
echo "Aberdefia - Anacleto";
} else if($nombrador == 'B') {
echo "Brígida - Brígido";
} else {
echo "Is that even a letter?";
}
Your code error near . you condition check variable name is $nombradorIf and also not declare variable but You assign the value variable name is $nombrador and you not use conditional operator == . so result not proper . You use above the code working fine
For checking conditional statement you have to use == (double equal sign) like below:
$nombrador=$_POST['nombrador'];
$nombrador=strtoupper($nombrador);
if ($nombrador == 'A') {
// ^^ Use like this
echo "Aberdefia - Anacleto";
} elseif ($nombrador == 'B') {
// ^^ Use like this
echo "Brígida - Brígido";
} else {
echo "Is that even a letter?";
}
I am using the following code to pass a variable. if variable = a, do nothing.
I then want to check if variable = a, do nothing, if b, do nothing, else do something
<?
if($_GET['pageid'] == 'a'){
} else {
include('header_image.php');
}
?>
Above is the code I have working correctly for one vartiable.
How do I add an if / else?
if($_GET['pageid'] != 'a' && $_GET['pageid'] != 'b'){
//do smth
}
This is a comment - i want the formatting...
To do what you want:
if ($_GET['pageid'] == 'a') {
// do nothing for now
}
elseif ($_GET['pageid'] == 'b') {
// do some more nothing...
}
else { // we do something...
include('header_image.php');
}
You could combine the 'do nothing' tests as:
if ( $_GET['pageid'] == 'a'
|| $_GET['pageid'] == 'b') {
// do nothing for now
}
else { // we do something...
include('header_image.php');
}
I agree it reads better than the 'not equal and' tests. However, that is what 'programmers' use so it is worthwhile getting used to it.
I need to check if $_POST['a'] is not empty AND is either '1' OR '2' so user cannot remove the a= or change the value from 1 or 2 to something else from the post path:
<?php
if(empty($_POST['a']) || !in_array($_POST['a'], array('1', '2'))) {
echo 'error1';
} else if ($_POST['a'] == '1') {
do something;
} else if ($_POST['a'] == '2') {
do something;
} else {
echo 'error2';
}
?>
Can anyone teach me how to do this in a correct way?
Many many thanks
You can use a switch instead:
switch ($_POST['a']):
case '':
// empty
echo 'error1';
break;
case '1':
// do something for 1
break;
case '2':
// do something for 2
break;
default:
// not empty but not 1 or 2
echo 'error2';
endswitch;
if (!empty($_POST['a']) && $_POST['a'] == '1') { //Not empty AND is 1
do something;
} else if (!empty($_POST['a']) && $_POST['a'] == '2') { //Not Empty AND is 2
do something;
} else {
echo 'error';
}
The first two will catch all "good" values, everything else will get the error. And no need for the top if in this case.
UPDATE: You have a syntax error. Missing a ) at the end of the first if.
Two easy ways of doing this:
// first condition should be by itself as it's a terminal error
if(empty($_POST['a']) or !in_array($_POST['a'], array('1', '2'))) {
echo 'error1';
die; // or redirect here or just enfore a default on $_POST['a'] = 1; // let's say
}
// Second can be like this or embraced in the else of the first one (se ex.2)
if ($_POST['a'] == '1') {
// do something;
} else if ($_POST['a'] == '2') {
// do something;
}
or
// first condition should be by itself as it's a terminal error
if(empty($_POST['a']) or !in_array($_POST['a'], array('1', '2'))) {
echo 'error1';
// or redirect here or just enfore a default on $_POST['a'] = 1; // let's say
}else{ // Second is in the else here :)
if ($_POST['a'] == '1') {
// do something;
} else if ($_POST['a'] == '2') {
// do something;
}
}
Your last else will not be reached as it will always end in the first if where you handle both emptiness and illegal value.